1. This invention relates to support members for circuit boards while terminal pins are being inserted. Particularly, the invention relates to large circuit boards such as are used for backplanes in telecommunications systems and other electrical and electronic systems.
2. Related Art
In many systems, smaller circuit boards, connectors, components and other items are mounted on circuit boards by the use of female terminals which connect with terminals pins in the main or large circuit board. Very often a large number of such terminal pins are inserted into a circuit board, and the actual pattern of the pins can vary according to the particular use of the board. Many of the pins will extend in rows across the board. Other pins may be in a random pattern. The pitch of the pins in a row, the spacing of the rows and the random pattern are all subject to variation. As the pins extend through the board, with a part of each pin extending on each side of the board, it is necessary to support the circuit board in such a manner that while firm support is provided, there is an opening in the support member into which a pin can enter on insertion. For pins in rows, a series of grooves can be cut in a support member. Different support members with differing spacing of grooves will be required, depending on the spacing of the rows. However, this is an inconvenience which can be accepted, although the problem of constantly changing support members to handle different boards is a nuisance, and can be dangerous if a mistake is made in selecting the support member. Very large numbers of backplane circuit boards are manufactured and the variety of circuit boards is also very large.
For the random pattern of pins, it is very difficult to cut grooves as they can overlap each other and result in a weak support member. Therefore, individual holes are often drilled into the support member to match the random pattern. This, again, gives rise to the possibility of the wrong support member being selected, as a different support member is required for each board design. A further complication is that in many instances the board has to be turned over for a repeat pin insertion step. This can require a further support member.